U.S. patent number 10,926,118 [Application Number 15/781,376] was granted by the patent office on 2021-02-23 for safety handle of fire extinguisher and fire extinguisher having the safety handle.
This patent grant is currently assigned to TOP ENGINEERING AND CONSTRUCTION CO., LTD.. The grantee listed for this patent is TOP ENGINEERING AND CONSTRUCTION CO., LTD.. Invention is credited to Seog Chae, Hojae Choi, Seongdae Choi, Seungwook Han, Kooksang Sim.
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United States Patent |
10,926,118 |
Choi , et al. |
February 23, 2021 |
Safety handle of fire extinguisher and fire extinguisher having the
safety handle
Abstract
A safety handle of a fire extinguisher includes a lower handle
coupled to an upper end of a valve and having a first hinge shaft
at one end thereof and a first support shaft parallel to the first
hinge shaft at a point spaced from the first hinge shaft. An upper
handle is coupled to the lower handle to be rotatable around the
first hinge shaft and downwardly rotate around the first hinge
shaft to push an open pin of the fire extinguisher. A second
support shaft is parallel to the first hinge shaft at one point. A
safety pin prevents the upper handle from rotating. A first link
having a first end of a length direction is coupled to the first
support shaft to be rotatable around the first support shaft. A
second link having a first end of a length direction is coupled to
the second support shaft.
Inventors: |
Choi; Hojae (Daegu,
KR), Han; Seungwook (Gumi-si, KR), Sim;
Kooksang (Gumi-si, KR), Choi; Seongdae (Gumi-si,
KR), Chae; Seog (Gumi-si, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
TOP ENGINEERING AND CONSTRUCTION CO., LTD. |
Gumi-si |
N/A |
KR |
|
|
Assignee: |
TOP ENGINEERING AND CONSTRUCTION
CO., LTD. (Gumi-si, KR)
|
Family
ID: |
1000005375377 |
Appl.
No.: |
15/781,376 |
Filed: |
May 24, 2016 |
PCT
Filed: |
May 24, 2016 |
PCT No.: |
PCT/KR2016/005462 |
371(c)(1),(2),(4) Date: |
June 04, 2018 |
PCT
Pub. No.: |
WO2017/131294 |
PCT
Pub. Date: |
August 03, 2017 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20190001168 A1 |
Jan 3, 2019 |
|
Foreign Application Priority Data
|
|
|
|
|
Jan 31, 2016 [KR] |
|
|
10-2016-0012049 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A62C
13/64 (20130101); A62C 13/76 (20130101); A62C
31/02 (20130101) |
Current International
Class: |
A62C
13/64 (20060101); A62C 13/76 (20060101); A62C
31/02 (20060101) |
Field of
Search: |
;169/89 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
20-2002-0003363 |
|
Apr 2002 |
|
KR |
|
20-0274902 |
|
May 2002 |
|
KR |
|
10-2002-0015090 |
|
Sep 2002 |
|
KR |
|
20-0288994 |
|
Sep 2002 |
|
KR |
|
10-1444688 |
|
Sep 2014 |
|
KR |
|
10-1524645 |
|
Jun 2015 |
|
KR |
|
10-1533302 |
|
Jul 2015 |
|
KR |
|
Primary Examiner: Lee; Chee-Chong
Attorney, Agent or Firm: Maschoff Brennan
Claims
The invention claimed is:
1. A safety handle of a fire extinguisher which includes a main
body with which fire extinguishing agents are filled and which has
a gushing mouth formed at an upper end of a main body for gushing
fire extinguishing agents, a valve arranged at the upper end of the
main body for opening and closing the gushing mouth, and an open
pin arranged at an upper side of the valve for opening the valve by
means of pressing, the safety handle comprising: a lower handle
which is coupled to the upper end of the valve and has a first
hinge shaft at one end thereof and a first support shaft parallel
to the first hinge shaft at a point spaced apart from the first
hinge shaft; an upper handle which is coupled to the lower handle
so as to swivel around the first hinge shaft, swivels downwards
around the first hinge shaft so as to press the open pin, and is
provided with a second support shaft parallel to the first hinge
shaft at one point; a safety pin for preventing the upper handle
from swiveling; a first link having a first end in the length
direction thereof coupled to the first support shaft so as to
swivel around the first support shaft; a second link having a first
end in the length direction thereof coupled to the second support
shaft so as to swivel around the second support shaft; and a second
hinge shaft to which a second end at the opposite side of the first
end of the first link, and a second end at the opposite side of the
first end of the second link are swivably coupled, wherein the
upper handle has first through hole penetrating both side walls of
a channel of the upper handle and formed at a point spaced apart
from the first hinge shaft, the lower handle has second through
hole penetrating both side walls of a channel of the lower handle
and formed at a point placed a same distance apart from the first
hinge shaft as a fourth through-holes of the upper handle, and the
second hinge shaft has a third through hole and wherein the first,
second and third through-holes are disposed at a same point in a
state where the upper handle does not swivel downwards, and the
safety pin is inserted into the first, second and third
through-holes.
2. The safety handle according to claim 1, wherein the second hinge
shaft is arranged out of the straight line connecting the first
support shaft and second support shaft.
3. The safety handle according to claim 1, wherein the second hinge
shaft has an external diameter larger than a diameter of the
through-holes of the upper handle and lower handle.
4. A fire extinguisher comprising a main body having a gushing
mouth for gushing fire extinguishing agents arranged at an upper
end thereof with which the fire extinguishing agents are filled, a
valve arranged at the upper portion of the main body for opening
and closing the gushing mouth, an open pin arranged at the upper
side of the valve for opening the valve by means of pressing, and a
safety handle according to claim 1.
5. A fire extinguisher comprising a main body having a gushing
mouth for gushing fire extinguishing agents arranged at an upper
end thereof with which the fire extinguishing agents are filled, a
valve arranged at the upper portion of the main body for opening
and closing the gushing mouth, an open pin arranged at the upper
side of the valve for opening the valve by means of pressing, and a
safety handle according to claim 2.
6. A fire extinguisher comprising a main body having a gushing
mouth for gushing fire extinguishing agents arranged at the upper
end thereof with which the fire extinguishing agents are filled, a
valve arranged at the upper portion of the main body for opening
and closing the gushing mouth, an open pin arranged at the upper
side of the valve for opening the valve by means of pressing, and a
safety handle according to claim 3.
Description
The present invention relates to a fire extinguisher and a safety
handle thereof and more particularly, to a safety handle with a
configuration in which when a fire extinguisher is used to
extinguish a fire, the safety pin coupled to the safety handle of
the fire extinguisher may be easily separated.
RELATED ART
A fire extinguisher is used to extinguish a fire at its initial
stage and has a structure in which fire extinguishing agents
accommodated in the fire extinguisher gush.
With reference to FIG. 1, the structure and operation of a
conventional fire extinguisher will be described.
A conventional fire extinguisher is filled with fire extinguishing
agents in the main body 10. The fire extinguishing agents filling
the main body 10 are discharged through a discharge pipe 11
arranged in the main body 10 and sprayed through a hose 12 at the
place where there is a fire.
Further, a valve 13 is installed between the discharge pipe 11 and
the hose 12 to open and close the discharge pipe 11, an opening pin
14 is installed at the upper side of the valve 13 such that the
valve 13 is opened to discharge the fire extinguishing agents from
the discharge pipe 11 to the hose 12 when the opening pin 14 is
pressed.
A safety handle 20 is coupled to the upper side of the valve and
consists of a lower handle 21 fixed to the upper side of the valve
13 and an upper handle 22 swivably coupled around a hinge shaft 23
fixed to the lower handle 21.
The opening pin 14 penetrates into the lower handle 21 to extend
towards the upper handle 22, and when the upper handle 22 is
pressed towards the lower handle 21, the upper handle 22 presses
the opening pin 14 such that the valve 13 is opened to gush the
fire extinguishing agents.
Meanwhile, each of the upper 22 and lower 21 handles has a through
hole in parallel with the hinge shaft 23. The through holes are
formed at a position where the upper handle 22 does not press the
opening pin 14, that is, a position where the through holes are
formed at a position where a path into which the thorough holes
penetrate into each other is formed, in the state where the through
holes are placed at the upper side, and a safety pin 24 is inserted
into the through holes.
Accordingly, even when the upper handle 22 is pressed in the state
where the safety pin 24 is inserted, the upper handle 22 does not
rotate with respect to the hinge shaft 23 and the opening pin 14 is
not pressed. However, when the fire extinguisher is used to
extinguish a fire, the safety pin 14 is pulled and removed, the
upper handle 22 is pressed, the upper handle 22 presses the opening
pin 14 and then, the valve 13 is opened to gush the fire
extinguishing agents.
Such a safety pin prevents the upper handle of the fire
extinguisher from being pressed by accident and prevents the fire
extinguishing agents from gushing without intention when the fire
extinguisher is not used. When the fire extinguisher is used, the
safety pin 24 is pulled and removed from the safety handle 20, and
afterwards, the upper handle 22 is pressed downwards so as to gush
the fire extinguishing agents from the fire extinguisher.
People learn how to use the fire extinguisher during fire drills
conducted by schools and the relevant authorities. However, despite
this, there are still may people who do not how to use the fire
extinguisher. In particular, people are often bewildered and
confused about how to use the fire extinguisher and finally cannot
use the fire extinguisher in an emergency such as a fire.
In particular, those who are not well-informed about a method of
using the fire extinguisher bring the fire extinguisher to a place
where there is a fire and often attempt to pull the safety pin in
the state where they strongly grip the safety handle.
When the safety handle 20 is strongly gripped, the upper handle 22
is pressed towards the lower handle 21, and the safety pin 24
receives a strong shearing force from the through holes of the
safety handle. Due to the shearing force, the safety pin 24 is not
pulled from the through holes even when the safety pin 24 is
strongly pulled.
DETAILED DESCRIPTION OF THE INVENTION
Technical Problems
As a means to solve the above-described problems with a fire
extinguisher having a conventional structure, provided is a safety
handle and a fire extinguisher having the same according to the
present invention which has the structure in which the safety pin
is easily removed even in the state where the safety handle is
strongly gripped and the upper handle is strongly pressed towards
the lower handle.
Technical Solutions
The above-described problems can be solved by using the present
invention in relation to a safety handle of a fire extinguisher and
a fire extinguisher having a safety handle.
The present invention relates to a main body having a gushing mouth
for spraying fire extinguishing agents arranged at the upper with
which fire extinguishing agents are filled, a valve arranged at the
upper portion of the main body for opening and closing the gushing
mouth, an open pin arranged at the upper side of the valve for
opening the valve by means of pressing, and a safety handle coupled
to the upper end of the valve, in which when the safety handle is
pressed, the open pin is pressed such that the fire extinguishing
agents in the main body gush, and in the state in which a safety
pin installed between an upper handle and a lower handle is not
removed, the safety handle is not pressed because of the safety
pin.
A safety handle of a fire extinguisher according to the present
invention comprises a lower handle which is coupled to the upper
end of a valve and has a first hinge shaft at one end thereof and a
first support shaft parallel to the first hinge shaft at a point
spaced apart from the first hinge shaft; an upper handle which is
coupled to the lower handle so as to swivel around the first hinge
shaft, swivels downwards around the first hinge shaft so as to push
the open pin, and is provided with a second support shaft parallel
to the first hinge shaft at one point; a safety pin for preventing
the upper handle from swiveling; a first link having a first end in
the length direction thereof coupled to the first support shaft so
as to swivel around the first support shaft; a second link having a
first end in the length direction thereof coupled to the second
support shaft so as to swivel around the second support shaft; and
a second hinge shaft to which a second end at the opposite side of
the first end of the first link, and a second end at the opposite
side of the first end of the second link are swivably coupled,
wherein through-holes are formed in each of the upper handle, the
lower handle, and the second hinge shaft, the through-holes are
disposed at the same point in the state where the upper handle does
not swivel downwards, and the safety pin is inserted into the
through-holes.
First, the operation of a safety handle and a fire extinguisher
having the same of the present invention with the above-described
configuration will be described.
The upper handle may swivel around the first hinge shaft with
respect to the lower handle. When the upper handle is pressed, the
upper handle presses an open pin to open a valve such that fire
extinguisher agents gush out of the main body of a fire
extinguisher.
However, the safety handle of the present invention has a
configuration in which the upper handle is selectively swiveled or
prevented from swiveling, and includes a linkage device and a
safety pin.
The first link is swivably coupled to the upper handle, and the
second link is swivably coupled to the lower handle. Because the
first and second links are swivably coupled to each other by a
second hinge shaft, when the upper handle is pressed, the upper
handle swivels around the first hinge shaft downwards. In this
case, the first and second links rotates in opposite directions to
each other, and the second hinge shaft moves in the direction of
the first hinge shaft or in the opposite direction of the first
hinge shaft.
Through-holes are formed at the upper handle, the lower handle, and
the second hinge shaft, and the safety pin is inserted into the
through-holes. In the state where the safety pin is inserted, the
second hinge shaft is prevented from moving so as to prevent the
first and second links from rotating such that the upper handle is
not pushed.
In the state where the safety pin is removed, when the upper handle
is pushed, a linkage device consisting of the first link, the
second link and the second hinge shaft does not interfere with the
operation of the upper handle.
Meanwhile, in terms of a fire extinguisher, the upper handle is
pushed to open the valve in the state where the safety pin is
removed. However, if the user does not know how to use such a fire
extinguisher or if the user is bewildered because of a fire, the
user might attempt to remove the safety pin in the state where the
user is gripping the safety handle, that is, in the state where the
upper handle is pressed against the lower handle.
In terms of the safety handle of the present invention, the
pressing force acting on the upper handle is delivered to the lower
handle through the first link, the second hinge shaft and the
second link, and only frictional force between the safety pin and
inner surfaces of the through-holes of the second hinge shaft and
the upper and lower handles acts on the safety pin by means of the
component of force of the pressing force acting on the upper
handle.
Such a component of force is a value obtained by multiplying a
value of force (F) acting on the first support shaft by means of
the upper handle by a sine value of an angle (.theta.) formed by
the straight line connecting the first and the second support
shafts and the straight line connecting the second support shaft
and the second hinge shaft. Accordingly, the component of force is
much smaller than force (F) acting on the first support shaft by
means of the upper handle.
As a result, in terms of the safety handle of the present
invention, even when the safety pin is removed in the state where
the upper handle is pressed, it takes a small amount of force to
remove the safety pin.
In particular, if the second hinge shaft is arranged close to the
straight line connecting the first support shaft and the second
support shaft, the angle (.theta.) is very small. Accordingly, the
component of force acting on the safety pin becomes smaller
depending on the force actin on the upper handle such that the
safety pin is more easily removed.
Advantageous Effects
According to the configuration and operation of the present
invention, even if the user does not know how to use the fire
extinguisher or if the user is bewildered because of a fire, the
user can easily remove the safety pin from the safety handle to
gush the fire extinguishing agents even in the state where the user
is gripping the safety handle and the upper handle is pressed.
BRIEF DESCRIPTION OF THE INVENTION
FIG. 1 is a perspective view illustrating a configuration of a
usual fire extinguisher.
FIGS. 2A and 2B are side views illustrating a safety handle of a
fire extinguisher according to an embodiment of the present
invention.
FIG. 3 is a view illustrating a safety handle of a fire
extinguisher according to an embodiment of the present invention
seen in the direction of the arrow of A in FIG. 2A.
FIG. 4 is a view illustrating the operation of a linkage device of
a safety handle of a fire extinguisher according to an embodiment
of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
The configuration and operation of a fire extinguisher according to
preferred embodiments of the preset invention will be described
hereunder with reference to the attached drawings.
A fire extinguisher according to this embodiment and the
conventional fire extinguisher illustrated in FIG. 1 are the same
except a safety handle. Accordingly, separate descriptions and
illustrations of the main body 10 and valve 13 of the fire
extinguisher according to this embodiment will be omitted.
Like safety handles of fire extinguishers according to related
arts, a safety handle 30 according to this embodiment basically
includes a lower handle 31 which is attached to the upper end of a
valve 13, into which an open pin 14 penetrates, and from which the
open pin protrudes, and an upper handle 32 which is swivably
coupled to the lower handle 31 by means of a first hinge shaft
33.
The detailed configuration and operation of a safety handle 30
according to this embodiment will be described with reference to
FIGS. 2A and 4. In FIGS. 2A and 4, illustrations of other
configurations such as a main body 10, a valve 13 and an open pin
14 etc. of the fire extinguisher except a safety handle will be
omitted for convenience's sake.
A safety handle 30 according to this embodiment includes a lower
handle 31 which is fixed to the upper side of the valve (13 in FIG.
1) and has a channel-shaped cross section, a first hinge shaft 33
which is provided at the end fixed to the upper end of the valve in
the lower handle 31, and an upper handle 32 whose one end is
swivably coupled to a first hinge shaft 33 so as to swivel with
respect to the lower handle 31 around the first hinge shaft 33 and
which has the same channel-shaped cross section as the lower handle
31 to extend. The first hinge shaft 33 is arranged across the
channel-shaped cross sections of the upper handle 32 and lower
handle 31.
With reference to FIG. 3, the upper handle 32 has through holes 321
penetrating both side walls of the channel and formed at a point
spaced apart from the first hinge shaft 33, and the lower handle 31
also has through holes 311 penetrating both side walls of the
channel and formed at a point placed the same distance apart from
the first hinge shaft 33 as the through-holes 421 of the upper
handle.
Meanwhile, the lower handle 31 has a first support shaft 312
installed between both side walls of the channel at a lower side in
the direction where the lower handle 31 swivels with respect to the
through holes 311 while the upper handle 32 has a second support
shaft 322 installed between both side walls of the channel at an
upper side in the direction where the upper handle 32 swivels with
respect to the through holes 321.
A first link 41 is swivably coupled to the first support shaft 312
of the lower handle 31, and in detail, a through opening 411 is
formed at the end of the first link 41, and the first support shaft
312 is inserted into the through opening 411.
A second link 42 is swivably coupled to the second support shaft
322 of the upper handle 32, and in detail, a through opening 421 is
formed at the end of the second link 42, and the second support
shaft 322 is inserted into the through opening 421.
A protrusion part 412 is formed at the end at the opposite side of
the first support shaft 312 at the first link 41 at both sides in a
lateral direction, and a through opening 413 is formed at the
protrusion part 412. A protrusion part 422 is formed at the end at
the opposite side of the second support shaft 322 at the second
link 42 at the center in a lateral direction, and a through opening
423 is also formed at the protrusion part 422.
The protrusion parts 412 of the first link and the protrusion part
422 of the second link are arranged to be complementary to each
other. Accordingly, the protrusion parts 412 of the first link and
the protrusion part 422 of the second link are placed in parallel
with each other as illustrated in FIG. 3.
The second hinge shaft 43 is inserted into the protrusion parts 412
of the first link and the protrusion part 422 of the second link
such that each end of one side of the first link 41 and the second
link 42 is swivably coupled to the lower handle 31 and the upper
handle 32, and the ends of the other side of the first link 41 and
the second link 42 are swivably coupled to each other such that the
first link 41 and the second link 42 rotate with respect to each
other.
The second hinge shaft 43 has a through hole 431 penetrating both
ends of the second hinge shaft in the length direction thereof.
In a non-operating state illustrated in FIG. 2A, that is, in the
state where the upper handle 32 is not pressed, the through holes
311, 321 of the lower handle 31 and the upper handle 32 are placed
at the same point while the through hole 431 of the second hinge
shaft 43 is placed at the same point as the through holes 311, 321,
of the upper and lower handles. As described, the through holes
311, 321, 431 are in parallel with one another, and a safety pin 50
is inserted into the through holes as illustrated in FIG. 3.
First, the operation of a safety handle will be described with
reference to FIG. 2B in the state where a safety pin 50 is removed
from a safety handle 30 of this embodiment, that is, in the state
where fire extinguishing agents are sprayed.
When the upper handle 32 is pressed to gush fire extinguishing
agents, the second support shaft 322 is pressed. Then, the
compressive pressure is consecutively delivered to the second link
42, the second hinge shaft 43 and the first link 41.
By means of the delivered compressive pressure, the first link 41
and the second link 42 rotate in the opposite direction, the second
hinge shaft 43 moves toward a position determined by the ends of
the rotating first link 41 and second link 42, that is, moves in a
direction where the second hinge shaft 43 moves far away from the
first hinge shaft 33.
As described above, when the user presses the upper handle 32 of
the safety handle 30 to operate the fire extinguisher, a linkage
device consisting of the first link 41, the second link 42 and the
second hinge shaft 43 put no obstacle to the operation of the
safety handle.
In the non-operating state of the fire extinguisher, the safety pin
50 is inserted into the through holes 311, 321 of the upper and
lower handles and the through hole 431 of the second hinge
shaft.
As described above, when the upper handle 32 is pressed in the
state where the safety pin 50 is inserted, the second support shaft
322 is pressed, and then, the compressive pressure is consecutively
delivered to the second link 42, the second hinge shaft 43 and the
first link 41. However, because the safety pin 50 is inserted into
the through holes 311, 321 of the upper and lower handles, the
second hinge shaft 43 may not move. Accordingly, the first link 41
and the second link may not swivel. Therefore, the upper handle 32
may not swivel downwards.
By means of the above-described operation, in the state where the
safety pin 50 is inserted, the upper handle 32 is not pressed.
Accordingly, the safety handle remains in the non-operation state
because of the safety pin 50.
Meanwhile, in this embodiment, even in the state where the upper
handle 32 is strongly pressed towards the lower handle 31, the
safety pin 50 may be easily removed when being strongly gripped.
The operation theory will be described below.
In this embodiment, the center of the second hinge shaft 43 is
arranged out of the line connecting the centers of the first
support shaft 312 and the second support shaft 322, which serve as
a center of the swivel movement of the first link 41 and the second
link 42.
When the second hinge shaft 43 is put on the straight line
connecting the first support shaft 312 and the second support shaft
322, the second link 42 and the first link 41 form a straight line
with respect to each other. In this state, when the safety pin 50
is removed and the upper handle 32 is pressed, the compressive
pressure is delivered through the second link 42 and the first link
41 to the lower handle 31, and there is the possibility that the
upper handle cannot rotate with respect to the first hinge shaft 33
while the state where the first link 41 and the second link 42 do
not rotate is maintained.
However, this does not happen to the safe handle of this embodiment
because the second hinge shaft 43 is arranged out of the straight
line connecting the first support shaft 312 and the second support
shaft 322.
Due to the arrangement of the second hinge shaft, the component of
force (Fx) with respect to the force (F) acting on the upper handle
32 causes frictional force which interferes with the removal of the
safety pin 50.
FIG. 4 illustrates only the first support shaft 312, the first link
41, the second hinge shaft 43, the safety pin 50, the second link
42 and the second support shaft 322 and illustrates the state in
which compressive force (F) acts on the second support shaft 322
when the upper handle 32 is pressed.
Force (F) applied to the second support shaft 322 acts in the
direction of the straight line connecting the centers of the second
support shaft 322 and the first support shaft 312. Such force (F)
is the total force of the component of force (Fy) in the length
direction of the second link 42 at the second hinge shaft 43
through the second link 42 and the component of force (Fx) in a
direction perpendicular to the component of force (Fy).
By means of the component of force (Fx), the second hinge shaft 43
is inclined towards a direction perpendicular to the length
direction of the second link 42. Because of this, the safety pin 50
inserted into the through hole 431 of the second hinge shaft 43 is
also inclined by the second hinge shaft 43 and is pressed towards
the edges of the through holes 311, 321 of the upper and lower
handles, and when the safety pin 50 is removed from the through
holes 311, 321, 431, frictional force is caused, which interferes
with the removal of the safety pin 50.
The component of force (Fx) in a perpendicular direction acting on
the safety pin 50 by means of the compressive force (F) is
described by the following formula. Fx=sin(.theta.).times.F
Herein, the angle ".theta." is formed by the straight line,
connecting the first support shaft 312 and the second support shaft
322, and the straight line connecting the second support shaft 322
and the second hinge shaft 43--i.e. the length direction of the
second link 42.
In this embodiment, the center of the second hinge shaft 43 is
arranged out of the straight line connecting the centers of the
first support shaft 312 and the second support shaft 322. Although
the angle ".theta." is not 0.degree., the angle ".theta." is very
small enough to arrange the second hinge shaft 43 slightly out of
the straight line connecting the centers of the first support shaft
312 and the second support shaft 322.
Accordingly, the component of force (Fx) in a perpendicular
direction acting on the safety pin 50 is very small depending on
force (F) pressed against the upper handle 32, and frictional force
acting on the safety pin is very small by means of the component of
force (Fx), thereby making it possible to easily remove the safety
pin in the state where the upper handle is pressed according to the
safety handle of this embodiment.
* * * * *